Thread-controlling mechanism for sewing-machines.



J. P. wBIs.

THREAD CONTROLLING MECHANISM FOR SEWING MACHINES.

' APPLIOATION FILED, MAY 13, 1907.

933,408. Patented Sept. 7, 1909.

3 SHEETS-SHEET 1. 4

WITNESSES:

J. P. WEIS. THREAD GONTROLLING MBQHANIQM FOR SEWING MACHINES.

Arrn'mnmn nnnn an 13, 1901.

Patntd Sept. 7, 1909.

3 SHEETS-SHEET 2.

WITNESSES.-

44- (Mn-AMA %W-- THREAD CONTROLLING MECHANISM FOR SEWING MACHINES.

APPLICATION FILED MAY 13, 1907.

933,408, Patented Sept. 7, 1909.

3 SHEETS-SHEET 3.

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UNITED s'rn rns PATENT orric JOHN P. WEIS, OF NYACK, NEW YORK, ASSIGNOB T 0 METROPOLITAN SEWING MACHINE COMPANY, OF 'NYACK, NEW YORK, A CORPORATION 'OF NEW YORK.

THREAD-CONTROLLING FOR SEWING-MACHINES.

933,408, Specification of Application filed May 13,

Letter P t n Patented Sept. 7, mos. 1907. Serial No. 373,245.

To all whom it may concern." v Be it known that I, J OHN P, VVnIs, a citizen of the United States, residing in Nvack, county of Rockland, and State of'New ork, have invented a new and useful Improvement in Thread-Controlling Mechanism for Sewing-Machines, of which the following is a description.

This invention relates to sewing machines, and particularly to thread controlling mechanism therefor. I

Among the objects of this invention may be noted the following: to provide a simple, compact and efficient mechanism by means of which the thread may be controlled in its passage to the stitchformingmeehanisni, in this instance, the looper of said niechan ism; to provide means whereby the thread may be measured o'fi" according to the requirements of the stitch-forming mechanism ;1 to provide means whereby the slack in the thread may be controlled and taken up dur ing the stitch-forming operation; to provide means whereby proper tension or grip may be applied to the thread in timed relation to the take-up and the pull-off; and to provide means whereby the thread in its passage to the stitching position may be con ducted so as to prevent contact with any of the driving parts of the ma'chine,such as the shafting,and may also be so guided and guarded as to prevent from being interfered with by the" work in its passage over the cloth-plate. a

With the above objects in View, and others which will be detailed during the course of this description, the invention consists inthe parts, features,- elements and combinations of elements as hereinafter described and claimed. I

In order that the invention may be clearly understood, the accompanying drawings are provided showing one form in which I, at

present, contemplate producing the same, and in said drawings: Figure 1 is area'r elevation of the well-known Metropolitan sew.- ing machine, part thereof being in section and so much thereof being shown as is deemed necessary to illustrate my invention,

which latter is shown applied thereto; Fig.

2 is a front elevation of the machine, with parts in section to clearly illustrate the manner in which the loop'er thread is controlled in its passage from the tension to the loo'per';

The loop'er-car'ri'er supports parts broken away to show certain details, and the View showing in top-plan the clothplate of the machine; Fig. 4 is a detail showing in side elevation the thread nipping device, and parts being shown in section; Fig. l 5 is a detached View showing in side elevation the thread take-up and a portion of the 1 thread guideyvhich cooperates with said take-up; and Fig. 6 is an elevation showing guide which cooperates with said pull-0E.

Referring to the drawings, the numeral 1 indicates the bed-plate of the machine, 2 the vertical portion of the arm thereof, 3 the overhanging portion of the arm, and 1 the bearings for theneedle and resser-bars.

The driving-shaft indicated by 5 and carries at one end the drivingpulley and balance-wheel 6, and at its other end carries the usual feed-eccentric 7, which, through the connections generally indicated by the numeral 8, operate the feed dog 9 in the usual manner. Near the pulley 6 the driving-shaft is provided with the usual eccentriclO, connected by the strap 11 to the short arm 12 of the needle-actuating lever, Which is fulcruined at 13 to the arm of the machine, and has the forwardly extending pols tion 14 connected by link 15 to the sleeve 16, clamped to the needle-bar 17, which latter carries the needle 18,-the latter being thus driven by the eccentric on the main shaft.v The needle-actuating leveris also provided with the depending 19, pivotally connectedat 20 to the pitman 21, in turn pivtedat its forward end to the loo'per-carrier 2'2, fulcrumed at 23 to the bed-plate 1 of the Zrnachi'ne, on a bracket 24 carried thereby. g a looper 25, :whi'ch may be of usual construction, such as is now common to the Metropolitan f two-thread chain-stitch seaming machine, he bearings 4 of the arm of the machine also receive the resser-bar 26, which carries at its lower enda resser-foot 27 of any suitable form, which cooperates with the I feed dog 9 to advance the work through the 'machin'e, The presser bar is depressed by means of the usual flat spring 26, the tension ofwhich is controlled by the adjusting v screw 26?. p g y The cloth-plate of the machine is indi- 'cated by 98, and has" set therein, in usual :rnanner; the throatplate 29, which extends Fig. 3 is a'sec'tionon line 3 '3 Fig. 2", with transverseiy thereof and through which the the pull-off and also a portion of the thread feed-dog and needle work, and said clothplate is also provided with a slide-plate 30, which slides in bearings extending lengthwise of the cloth-plate and which closes an opening through which access to the looper may be had and through which the looper is threaded. The cloth-plate also has, extending transversely thereof, the threadgroove 31, which extends from the slideplate 30 to the thread-eye or guide 32, set vertically in the cloth-plate, and which is open at one side, as indicated at 33, thus causing its central bore to be formed in continuity with the slot 34, which extends from said thread-eye or guide to the rear edge of the cloth-plate. On the bottom of the clothplate is secured, by means of a screw, rivet, or in any other suitable manner, a threadguide 35, in this instance shown as a finger extending into the opening in the clothplate, which is covered by the slide-plate 30, said finger being provided with a thread-eye or guide 36, located substantially in aline ment with the groove 31 in the cloth-plate, whereby the thread, indicated by w, may be led through the groove and then downwardly through the eye 36 and from thence to the looper 25, through the eyes of which it is threaded in the usual manner.

The driving-shaft 5 is provided with an eccentric 37 which is surrounded by a strap 38, the arm of which extends to a crank 39, carried by a rock-shaft 40, journaled in a bearing 41 carried by the bed-plate of the machine, said rock-shaft having secured thereto, at its end adjacent the crank 39, a take-up arm 42, extended vertically to a position close to the bottom of the cloth-plate 28. The take-up arm is provided at its upper end with a thread-guide 43 and is secured to its rock-shaft at its lower end by means of being split longitudinally and clamped to said rock-shaft by the screw 44. The other end of the rock-shaft 40 has clamped to it a pull-off arm 45, clamped to said rock-shaft in manner similar to the take-up arm 42, said pull-01f arm 45 being provided with a flattened face 46, which engages the thread as hereinafter described. The arm 2 of the machine, near the bedplate 1 and between the take-up and pulloif arms, is provided with a substantially Y shaped bracket, one arm 47 of which is provided with a U-shaped end 48, extending horizontally under the cloth-plate, and arranged so as to allow the take-up arm 42 to operate between its two arms 49, 49, each of said arms being provided with a threadeye 50. The other arm 51 of the bracket is provided with a similar U-shaped, horizontally extending portion 52, between the arms 53 of which the pull-off lever 45 operates, and which arms are provided with the threadeyes for guiding the thread. The arms which cooperate with the take-up are extended toward the front of the machine, while the arms which cooperate with the pull-01f are extended toward the rear of the machine; and said take-up and pull-off arms are arranged on the rock-shaft 40 in such manner that the take-up action and pull-01f action will occur simultaneously, such action being produced during the movement of said arms in the general direction of the front of the machine. The bracket carrying the two arms 47 and 51 is secured to the arm 2 by means of the screws 54, which pass through the vertical portion of said bracket and are tapped into the arm of the machine. This bracket is also provided with an arm 55, located between the two arms 47 and 51, which arm 55 forms a part of a thread-clamp or nipperand may be resilient if desired, said arm extending vertically or parallel with arm 2 of the machine and constituting the stationary aw of the thread-clamp or nipper.

The movable or clamping jaw of the nip per is indicated by 56, and consists of a fiat blade extending at a right-angle to its supporting shank 57, which latter is socured by means of screws 58, for example, to the arm 59, journaled upon the rockshaft 40, said arm 59 being one portion of a bell-crank lever, presently described. The supporting shank 57 is also provided with a projection or finger 57 extending at a right-angle to the jaws 55-5(3 and of sufficient length to at all times extend past the jaw 55. The location of finger 57 is above the bottom of the clamping-jaws and said finger acts as a thread-rest or support and holds said thread between the clamping jaws. This is an important feature of my invention, since it prevents the escape of the thread through the bottom of the clamp and insures its proper position in the clamp and the function of the latter. The other arm 60 of the bell-crank is extended toward the driving-shaft 5 of the machine, and is provided with a yoke composed of the rigid arm 61, and the yielding arm (32, which embraces the cam 63, carried by the drivingshaft. The yielding arm 62 is secured to the arm 60 of the bell-crank lever by means of screws 64, the same thus compensating for varying sizes of eccentrics which may be employed, or for any grit or other substance which may be deposited upon the cam, and which might produce objectionable wearing action upon the latter. This cam 3 is what may be termed a two-phase cam, since it has the two concentric portions connected by cam projections which result in rocking the bell-crank nipper-lever in timed relation to the rocking action of the pull-01f and take-up cams.

The arrangement of the cam (33 and eccentric 37,0r timing, as it is commonly called,is such as to cause the thread 02 to be gripped ornipped between the two clamp ing-jaws 55 and 56 just before the pull-off and take-up arms begin their operations to, on the one hand, pull the thread from the supply or tension of the machine, and on the other hand, take up the slack in said thread, which extends between the threadclamp or nipper and the looper, such slack occurring during the backward movement of the latter. Thus, it will be seen that provision is made not only for pulling off or measuring the required amount of thread to be consumed in making the stitch, but the slack, which occurs during the backward movement of the looper between the latter and the nipper, will be taken up and controlled so as to prevent the same from becoming entangled in any manner, or falling upon or engaging with oiled or dirty parts. Hence, the thread is under perfect control at all times during the operation of the machine and is prevented from becoming soiled.

The above description shows clearly that the thread is led from the supply through the tension 65, thence. through the guideeyes 53 in the arms 53 in front of the pulloff arm 45, thence between the two jaws 55 and 56 of the clamp or nipper and over the thread-rest, and thence through the eye 50 of one of the arms 49, then through the eye 43 of the take-up arm 42, and then through the thread-eye 50 of the other arm 49. At this point the thread is drawn to the rear of the machine and passed into the outer end of'the slot 34, by lifting the thread vertically, and is then drawn toward the front of the machine, so as to place the same within the guide 32, and then" said thread is laid in the groove 31 of the cloth-plate, and then passed through the eye 36 of the guide 35, and then threaded into the looper. Thus, it will be seen that the thread is not allowed to contact with any part of the machine which is liable to apply friction thereto, or which is liable to soil the same and, when passing'over the clothplate, lies embedded in the latter so as to prevent the work passing over the same from engaging and accidentally pulling it, said thread being thus led to the looper, or other lower thread-carrying device, which may be either a looper or a spreader, without appearing above the surface of the cloth-plate, and yet being in convenient position for manipulation should the thread break or the loop-er become unthreaded, or should an. accident of any character occur to the thread. This mode of conducting and controlling the thread is one of the important features of my invention, and upon it I desire to lay stress. Likewise I desire to lay stress upon the importance of the combinative arrangement and functional cooperation of the thread-clamp, pull-off and take-up, as well as the arrangement of the thread-controlling mechanism, as a whole, with reference to the thread-guiding means, consisting of the slot 34, guide-eye 32, groove 31, and guide 35, whereby control of the thread is had and maintained at all times, and whereby the thread is always in convenient position for re threading the machine, and whereby the machine originally can be easily threaded without tilting the same, or being compelled to go behind it, or assume any other awkward position with reference to the machine, as is now common.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. In combination with the cloth-plate of a sewing machine having an opening therein for access to the looper of the machine, a thread-guide carried by the cloth-plate and extending into said opening, a guide-eye carried by the cloth-plate, and a thread-guiding means extending between said guide and guide-eye whereby the thread may be led across the cloth-plate to the lower threadcarrying device of the machine.

2. In combination with the cloth-plate of a sewing machine having an opening therein for access to the lower thread-carrying device, a thread-guide extending into said opening, the surface of said cloth-plate being provided with a thread-groove extending from said opening toward the rear edge of said plate, a guide-eye embedded in the cloth-plate at the end of said groove, and said cloth-plate having a slot extending from said guide-eye to the rear edge thereof.

3. A thread-controlling mechanism for sewing machines comprising a thread-clamp and a take-up, in combination with means for guiding thread to the lower thread-carrying device of the stitch-forming mechanism, said guiding means comprising a clothplate and a thread-eye in the cloth-plate, an open-end slot in the cloth-plate leading to said thread-eye, and a groove in the clothplate leading from said thread-eye to approximately the position of operation of the lower thread-carrying device of the said stitch-forming mechanism.

4. A thread-controlling mechanism for sewing machines comprising the cloth-plate of the machine having an opening therein for access to the lower thread-carrying device of the stitch-forming mechanism, a groove in the upper surface of the cloth-plate extending from said opening toward the rear edge of the cloth-plate, a guide at one end of saidgroove, and a guide-eye at the other end of said groove, both in alinement with the latter, and an open-end slot in the clothplate connecting with the said guide-eye, in combination with thread-controlling mechanism.

5. A thread-guiding means for sewing ing a thread-eye arranged in alinement with machines COIIIPIlSiIl a groove in the surface said groove, substantially as described. of the cloth-plate of said machine, the same In testimony whereof I have hereunto extending transversely of said cloth-plate signed my name in the presence of two sub- 5 and terminating near the rear edge of the scribing Witnesses.

latter an open-end slot in said cloth-plate 1 commimicating With said groove, a guide- JOHN VVILIS' eye set in the cloth-plate having one side Vitnesses:

open and communicating With said slot, and FRITZ BENDER,

10 a guide at the other end of said groove hav- LULU M. Gnoss. 

